I was sitting in the cockpit while my friend ( who owned the aircraft) was starting the engine on a Taylorcraft. A continental, can't remember if it was 65 or 90 hp. It was being very reluctant to start, lots of cursing, mags on and off, sucking in, priming, the usual hand swinging stuff. Eventually we thought we were getting somewhere when it decided to cough a couple of times, so "one more prime" he says "mags on" and another swing.
Which was when it caught fire.
He informed me of this fact, quite calmly, so I did the obvious thing and got out. I then sacrificed what had been a perfectly good hat to stifling the not very impressive flames.
The aircraft didn't seem to take any great harm from this, which is more than I could say for the hat, the only flat cap I have ever owned that was comfortable with a headset.
OTOH, I once managed to start an O-360 straight out of the hangar, -15c, mixture idle cut off, fuel and mags off, (keys in my pocket) four blade prop, by pulling it through prior to what I anticipated would be a difficult start. Good job we had a standing rule at that club to always chock the wheels when parked. Yep, hot mag.
Things like that just don't happen with cars, do they?